1. Field of the Invention
The present invention relates to a turret punch press, and more specifically to a turret punch press, by which angular positions of a plurality of punches and dies arranged on upper and lower turrets can be indexed, respectively.
2. Description of the Background Art
In the conventional turret punch press, a plurality of punches and dies are arranged on an upper and lower turrets of the same diameter, respectively, and further only a pair of punch and die arranged so as to be opposed to each other among the other pairs are indexed, as an indexed die, with a well-known indexing mechanism. Therefore, the punches and the dies other than the indexed die are usually indexed manually by the worker, without being automatized.
In more detail, since the diameters of the upper and lower turrets are the same in both, although it may be possible to raise the upper turret upward in order to index the punches, it is impossible to raise the lower turrets upward in order to index the dies because the upper turret is positioned over the lower turret. Accordingly, it has been necessary to index the die from the circumferential side of the lower turret, with the result that the automatic mechanism for indexing the dies is strictly restricted in space and therefore is complicated in construction when automatized. In other words, it has been so far difficult to automatize the indexing work of the dies in practice.